Explosion-engine.



PATENTBD 00T. 13,-'1-903.

I". H. SMITH. EXPLOSION BNGINII APPLIATION FILED FEB. 4|vl903f.

N0 MODEL.

No. 741,559. l

UNITED STATES PATENT OFFICE.

Patented October 13, 1903.

`FREDERICK HUGH SMITH, OF DATCHET, NEAR WINDSOR, ENGLAND.

EXPLOSION-ENGINE.'

SPECIFICATION forming part of Letters Patent No. 741,559, dated October 13, 1903.

Application led February 4, 193. Serial No. 141,902. (No model.) l

1b all whom it may concern:

Be it known that I, FREDERICK HUGH SMITH, engineer, a subject of the .King voi Great Britain, residing at Manor House, Datchet, near Windsor, England, have invented certain new and useful Improvements in Explosion-Engines, of which the following is a specification. Y

This invention relates to that class of explosion-engine in which there is a supplementary piston behind the main piston, the two pistons moving/together during the outstroke, but the'supplementary piston returning before the main piston,` sweeping out before it the products of combustion while the new charge is supplied between the two pistons,kthere being a non-return valve in thefsupplementay piston, through which the charge is forced into the inner end of the cylinder on the return of the main piston. Such engines are described in the specification Vof my Patent No. 636,298.

According to the present invention I provide a closed chamber, 4 which maybe the outer end of the cylinder, combined or not with a crank-chamber, into which the explosive mixture is drawn through a non-return valve by the inward movementl of the main piston and in which it is partially compressed by its outward movement. In the main piston also I provide a non-return valve,through which the charge passes when the pressure in the cylinder is reduced by openingthe exhaust, so that the charge forces the supplementary piston to the end of the cylinder and causes it to sweep out the products of combustion, as above described. The main piston then comes back and forces the charge through the valve in the supplementary piston and compresses it into the inner end of the cylinder.

Figure l is a vertical section of anl engine constructed according to this invention, and Fig. 2 shows a detail.

a is the cylinder.

b is the main piston. c is the connectingrod, pivoted to it.

d is the crank shaft, and e is the supplelmentary piston, 'working loose in the cylinder.

f is the exhaust-valve, worked in the usual way by a cam g, xed tothe crank-'shaft d.

h is a crankchamber open to the outer end of the cylinder.

' liis anon-return valveadmitting the explosive mixture into the chamber h.

2c is a non-return valve Working in a recess in the main piston b, and Z is a spring forcing it against its seat. The travel of the 4valve lc is limited by an annular plug m, having holes or ports 'n in it, which is screwed into the recess in the piston b.

o is a non-return valve in the piston e, and p is a spring tending to'force it onto its seat. q is another spring, preferably stronger than p, which acts as a buffer for the boss on the valve-stem when the valve is suddenly opened. The length of the spring q is such that it does not act on the valve when closed.

.When the partsare in the positions shown, the exhaust-valve f has just closed and the piston b is about to move toward the inner end of thefc'ylinder a, and in so doing it will d raw explosive mixture vthrough the valve j intoY the chamber h and will compress the mixture which is between the pistons and will ultimately force itjthroughthe valve o to the other side of the pistone. When the piston b reaches the end of itsinstroke, the

explosion takes place and the pistonsb and` c are forced outward together, compressing the mixture in the chamber h. Toward' the end of the outstroke the exhaust-valve f isV opened and the pressure in the inner end of ythe cylinder falls, whereupon the mixture in the chamber h,fwhich is at a higher-pressure than atmospheric, flows through the valve lo,

forcing the piston e toward theinner end of the cylinder, so sweeping out the products of combustion. The valve f then closes, and

the parts are again in the positions shown,

too 

